Depending on the processed material from each drill must be properly sharpened. To verify the correct angle will help a specially prepared square plate of copper or aluminium with a thickness of 1 mm.
To become operational protractor enough to cut it cut, as shown in the picture: a large cutout at an angle of 120 degrees, the other half is 60 degrees and the surviving corner of a square is 90.
Recommend to read
ANTONOV AN-70
An-70 medium — range cargo (operational-tactical military transport) aircraft of the new generation of short take-off and landing. Antonov an-70 intended to replace the obsolete An-12....
TILLERS SIBIRYAK
Simplicity in manufacture and maintenance, reliability, versatility— these are the qualities that I wanted to achieve by producing tillers. Now, after two years of operation at the farm,...